Is a four leafed clover a mutation of the common three leafed clover

Its relative rarity suggests a possible recessive gene appearing at a low frequency. Alternatively, four-leaf clovers could be caused by somatic mutation or a developmental error of environmental causes. They could also be caused by the interaction of several genes that happen to segregate in the individual plant. It is possible all four explanations could apply to individual cases.

if all the leaves are four-folioled it may be mutation. if one leaf is four on 3-leafed plants it's not